Add Bastian Kersting to Exploit Mitigations PG

Adds Bastian Kersting to the list of members in the Exploit Mitigations
PG.

Author: rcvalle

teams/project-exploit-mitigations.toml

@@ -7,6 +7,7 @@ leads = [
     "rcvalle",
 ]
 members = [
+    "1c3t3a",
     "cuviper",
     "rcvalle",
 ]